Currently, radio links are widely used for accessing the wireless LAN or mobile phone base stations, as an easy solution to be implemented and at a competitive cost.
However, the telecommunications market calls for a continuous increase of its capacities and lower costs.
This increase in the requested capacities is facing the limits of the occupation of the spectra, the existing technologies and the cost that all this involves.
Currently there are three ways to increase the net capacity:    1) To increase the levels of modulation, that causes problems of linearity and sensitivity against the noise. The current limit is in the 256QAM.    2) To increase the bandwidth, which is internationally regulated, and only allows high bandwidth for links from 60 to 80 GHz and at these frequencies the distances of these links are unacceptably short, therefore it is not viable.    3) To double the capacity using two different links, both operating at the same frequency with cross polarizations. This possibility is rarely used by being very complex and expensive. Regarding this third point, the most used solution consist of coupling a single antenna to two transceiver units (transmitter and receiver), one which works with vertical polarization and one which works with horizontal polarization, through an orthogonal mode transducer module (OMT, Orthogonal Mode Transducer) that separates the vertically polarized waves from the horizontally polarized waves.
The two transceiver units are controlled by a single input control unit known as an In-Door Unit (IDU), which has a very expensive and complex configuration.
Therefore, this solution requires for each of the two terminals that make up a radio link, an IDU, two radio units, an OMT module and an antenna, which is a complex, costly and unreliable device.
The invention doubles the capacity of radio links, in accordance with paragraph 3, only by means of a single transceiver unit with the cross polarization multiplexer included therein and an antenna, which eliminates the need to use a second transceiver unit, the OMT external module and the IDU unit, which considerably simplifies the structure of this type of devices and significantly reduces their cost.